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// DogToy.h
@interface DogToy : RLMObject
@property NSString *name;
@end
// Dog.h
@interface Dog : RLMObject
@property NSString *name;
@property int age;
@property NSString *color;
// To-one relationship
@property DogToy *favoriteToy;
@end
// Enable Dog for use in RLMArray
RLM_COLLECTION_TYPE(Dog)
// Person.h
// A person has a primary key ID, a collection of dogs, and can be a member of multiple clubs.
@interface Person : RLMObject
@property int _id;
@property NSString *name;
// To-many relationship - a person can have many dogs
@property RLMArray<Dog *><Dog> *dogs;
// Inverse relationship - a person can be a member of many clubs
@property (readonly) RLMLinkingObjects *clubs;
@end
RLM_COLLECTION_TYPE(Person)
// DogClub.h
@interface DogClub : RLMObject
@property NSString *name;
@property RLMArray<Person *><Person> *members;
@end
// Dog.m
@implementation Dog
@end
// DogToy.m
@implementation DogToy
@end
// Person.m
@implementation Person
// Define the primary key for the class
+ (NSString *)primaryKey {
    return @"_id";
}
// Define the inverse relationship to dog clubs
+ (NSDictionary *)linkingObjectsProperties {
    return @{
        @"clubs": [RLMPropertyDescriptor descriptorWithClass:DogClub.class propertyName:@"members"],
    };
}
@end
// DogClub.m
@implementation DogClub
@end

class DogToy: Object {
    @Persisted var id: ObjectId
    @Persisted var name = ""
}
class Dog: Object {
    @Persisted var name = ""
    @Persisted var age = 0
    @Persisted var color = ""
    @Persisted var currentCity = ""
    @Persisted var citiesVisited: MutableSet<String>
    @Persisted var companion: AnyRealmValue
    // To-one relationship
    @Persisted var favoriteToy: DogToy?
    // Map of city name -> favorite park in that city
    @Persisted var favoriteParksByCity: Map<String, String>
    
    // Computed variable that is not persisted, but only
    // used to section query results.
    var firstLetter: String {
        return name.first.map(String.init(_:)) ?? ""
    }
}
class Person: Object {
    @Persisted(primaryKey: true) var id = 0
    @Persisted var name = ""
    // To-many relationship - a person can have many dogs
    @Persisted var dogs: List<Dog>
    // Inverse relationship - a person can be a member of many clubs
    @Persisted(originProperty: "members") var clubs: LinkingObjects<DogClub>
    // Embed a single object.
    // Embedded object properties must be marked optional.
    @Persisted var address: Address?
    convenience init(name: String, address: Address) {
        self.init()
        self.name = name
        self.address = address
    }
}
class DogClub: Object {
    @Persisted var name = ""
    @Persisted var members: List<Person>
    // DogClub has an array of regional office addresses.
    // These are embedded objects.
    @Persisted var regionalOfficeAddresses: List<Address>
    convenience init(name: String, addresses: [Address]) {
        self.init()
        self.name = name
        self.regionalOfficeAddresses.append(objectsIn: addresses)
    }
}
class Address: EmbeddedObject {
    @Persisted var street: String?
    @Persisted var city: String?
    @Persisted var country: String?
    @Persisted var postalCode: String?
}

// Get a specific person from the default realm
Person *specificPerson = [Person objectForPrimaryKey:@12345];

let realm = try! Realm()
let specificPerson = realm.object(ofType: Person.self, forPrimaryKey: 12345)

RLMRealm *realm = [RLMRealm defaultRealm];
RLMResults *dogs = [Dog allObjectsInRealm:realm];
RLMResults *people = [Person allObjectsInRealm:realm];

let realm = try! Realm()
// Access all dogs in the realm
let dogs = realm.objects(Dog.self)

let realm = try! Realm()
// Access all dogs in the realm
let dogs = realm.objects(Dog.self)
// Query by age
let puppies = dogs.where {
    $0.age < 2
}
// Query by person
let dogsWithoutFavoriteToy = dogs.where {
    $0.favoriteToy == nil
}
// Query by person's name
let dogsWhoLikeTennisBalls = dogs.where {
    $0.favoriteToy.name == "Tennis ball"
}

let realm = try! Realm()
// Access all dogs in the realm
let dogs = realm.objects(Dog.self)
// Filter by age
let puppies = dogs.filter("age < 2")
// Filter by person
let dogsWithoutFavoriteToy = dogs.filter("favoriteToy == nil")
// Filter by person's name
let dogsWhoLikeTennisBalls = dogs.filter("favoriteToy.name == 'Tennis ball'")

RLMRealm *realm = [RLMRealm defaultRealm];
// Access all dogs in the realm
RLMResults *dogs = [Dog allObjectsInRealm:realm];
// Filter by age
RLMResults *puppies = [dogs objectsWhere:@"age < 2"];
// Filter by favorite toy
RLMResults *dogsWithoutFavoriteToy = [dogs objectsWhere:@"favoriteToy == nil"];
// Filter by favorite toy's name
RLMResults *dogsWhoLikeTennisBalls = [dogs objectsWhere:@"favoriteToy.name == %@", @"Tennis ball"];

let realm = try! Realm()
let dogToys = realm.objects(DogToy.self)
// Get specific user by ObjectId id
let specificToy = dogToys.where {
    $0.id == ObjectId("11223344556677889900aabb")
}

let realm = try! Realm()
let dogToys = realm.objects(DogToy.self)
// Get specific toy by ObjectId id
let specificToy = dogToys.filter("id = %@", ObjectId("11223344556677889900aabb")).first
// WRONG: Realm will not convert the string to an object id
// users.filter("id = '11223344556677889900aabb'") // not ok
// users.filter("id = %@", "11223344556677889900aabb") // not ok

RLMRealm *realm = [RLMRealm defaultRealm];
// Establish a relationship
Dog *dog = [[Dog alloc] init];
dog.name = @"Rex";
dog.age = 10;
Person *person = [[Person alloc] init];
person._id = 12345;
[person.dogs addObject:dog];
[realm transactionWithBlock:^() {
    [realm addObject:person];
}];
// Later, query the specific person
Person *specificPerson = [Person objectForPrimaryKey:@12345];
// Access directly through a relationship
NSLog(@"# dogs: %lu", [specificPerson.dogs count]);
NSLog(@"First dog's name: %@", specificPerson.dogs[0].name);

let realm = try! Realm()
// Establish a relationship
let dog = Dog()
dog.name = "Rex"
dog.age = 10
let person = Person()
person.id = 12345
person.dogs.append(dog)
try! realm.write {
    realm.add(person)
}
// Later, query the specific person
let specificPerson = realm.object(ofType: Person.self, forPrimaryKey: 12345)
// Access directly through a relationship
let specificPersonDogs = specificPerson!.dogs
let firstDog = specificPersonDogs[0]
print("# dogs: \(specificPersonDogs.count)")
print("First dog's name: \(firstDog.name)")

RLMRealm *realm = [RLMRealm defaultRealm];
// Establish a relationship
Person *person = [[Person alloc] init];
person._id = 12345;
DogClub *club = [[DogClub alloc] init];
club.name = @"Pooch Pals";
[club.members addObject:person];
[realm transactionWithBlock:^() {
    [realm addObject:club];
}];
// Later, query the specific person
Person *specificPerson = [Person objectForPrimaryKey:@12345];
    
// Access directly through an inverse relationship
NSLog(@"# memberships: %lu", [specificPerson.clubs count]);
NSLog(@"First club's name: %@", [specificPerson.clubs[0] name]);

let realm = try! Realm()
// Establish an inverse relationship
let person = Person()
person.id = 12345
let club = DogClub()
club.name = "Pooch Pals"
club.members.append(person)
try! realm.write {
    realm.add(club)
}
// Later, query the specific person
let specificPerson = realm.object(ofType: Person.self, forPrimaryKey: 12345)
// Access directly through an inverse relationship
let clubs = specificPerson!.clubs
let firstClub = clubs[0]
print("# memberships: \(clubs.count)")
print("First club's name: \(firstClub.name)")

// Open the default realm
let realm = try! Realm()
// Get all contacts in Los Angeles, sorted by street address
let losAngelesPeople = realm.objects(Person.self)
    .where {
        $0.address.city == "Los Angeles"
    }
    .sorted(byKeyPath: "address.street")
print("Los Angeles Person: \(losAngelesPeople)")

// Open the default realm
let realm = try! Realm()
// Get all people in Los Angeles, sorted by street address
let losAngelesPeople = realm.objects(Person.self)
    .filter("address.city = %@", "Los Angeles")
    .sorted(byKeyPath: "address.street")
print("Los Angeles Person: \(losAngelesPeople)")

RLMRealm *realm = [RLMRealm defaultRealm];
RLMResults<Contact *> *losAngelesContacts = [Contact objectsInRealm:realm where:@"address.city = %@", @"Los Angeles"];
losAngelesContacts = [losAngelesContacts sortedResultsUsingKeyPath:@"address.street" ascending:YES]; 
NSLog(@"Los Angeles Contacts: %@", losAngelesContacts);